Deltaform Mountain
                
                3424m, 11233ft
                
                August 12 2025
                
                Standing high and intimidatingly above the Valley of the Ten Peaks is Deltaform Mountain, a sharp mass of rock making up one of the 11000ers present in the Lake Louise area and one of the ten namesake peaks surrounding the valley. With the standard NW ridge route rated 5.5-5.6 Deltaform is one of the more difficult ascents on Bill Corbett's list and with the easiest route climbing up and over Neptuak Mountain in order to access it the ascent is quite committing. While the climbing comes in steps allowing the way up to be compartmentalized, the nose pitch at the base of Neptuak and the notch just before the summit of Deltaform prove to be sizable challenges to overcome, and with the descent being the reverse of the entire route a push for Deltaform requires a long day if not multiple days of focus.
                
        
                I'd been aware of Deltaform for a number of years before this trip and always knew it was a technical peak to check off but when it came to the actual day we went for it the segmented climbing phases made it feel quite manageable and it definitely wasn't the gripping horror show I was expecting. That being said the situation Troy and I ended up getting into on the way down turned an enjoyable and relatively straightforward day in the alpine into a quite serious situation and we had to be efficient to get out of technical terrain before weather hit and getting benighted, more on that later! 
                
                After a long day out on
                Assiniboine and Lunette
                a couple days prior the legs were feeling it but an opening in the forecast was looking promising and with objectives finally starting to dry out after a heavy precip summer Troy and I committed to our plans of going for Deltaform in a single push and met up early on the morning of August 12th to head for Lake Louise. With the annoyance of how difficult it can be to book a shuttle up to Moraine Lake these days and the road's closure to public vehicles we had just planned to bike from downtown Lake Louise so after arriving a bit after 5am we got the bikes ready and at 5:30 we started the 15km bike up.
                
                The bike up was simple but a leg burner as usual and after a bit over an hour we were at the lake and locked up the bikes before starting the hike to Wenkchemna Pass. Neither of us had ever been to this pass having only done Sentinel Pass and although it's 10km it went by quickly and in the clear weather that we had the views were phenomenal. It was hard not to get excited with our objective in the forefront of our view as we got closer and with great trail we made good time reaching the pass just before 9am.
                
                
                    
                
                
                links: 
                STRAVA
                |
                GAIA
                
                elapsed time: 22hrs
                
                DIFFICULTY: climbing - 5.5-5.6, sustained 5th class, committing, often multiday
                
      
      
    
      
      
    
    
      
      
  After reaching Wenkchemna Pass, taking a break, and getting our climbing gear on we started making our way towards the sharp initial ridge of Neptuak. The first pitch called the "nose pitch" is a bit climber's right of the ridge arête and after a bit of traversing and scrambling we could see where we had to go and it was steep! We both thought this section was quite vertical for the grade so we opted to rope up for this section and tat was quite good which was the case for the entire route which eased things quite a bit. 
  
  Following the nose pitch we scrambled a bit further before reaching the ridge and the next section was scree and some light hands on terrain for a good portion before eventually reaching the second steep feature a few hundred meters above which we opted to protect as well. After this ridge climb feature the terrain got quite blocky and we both felt comfortable so we soloed through this with a few airy moves along the way and next up was the black band. 
  
  The black band had more loose scree on top of solid rock than the other sections of the Neptuak ascent so we had to be careful of rockfall here but after a bit of hands on terrain and a short chimney section we had topped out and were on the final summit ridge to the top of Neptuak.
    
      weakness
      
      
      
      
      
      
      
    the giants in sight
    
      but still exposed
      
    
      
      
      in many reports
      
    
    
    
    After a couple minutes at the top admiring Deltaform and how intimidating it looks from afar we started working our way down and were quickly met with some 4th to low 5th terrain we had to downclimb but felt quite manageable. Following this section the first oddly flat portion of the Neptuak-Deltaform col starts and this is where we should've headed right around a west buttress feature to avoid a steep section to reach the next flat portion. The following section would've been a difficult downclimb and we didn't feel like retracing our steps to find the bypass so we opted for a quick rappel which was fun but we lost a few minutes here. Following that we were at the proper col and it was time to start climbing Deltaform Mountain!
    
      
      
    feature
    
    
    
  The Deltaform Mountain ascent was nicely divvied up into technical 5th class sections around 5.2-5.4 and walking portions so it was a lot easier than it looked from neptuak and with some of the rappel stations bolted there isn't much to worry about reversing this section. After climbing for a while we were getting closer to the bulky summit block which didn't appear to be looking any easier as we approached but before things get vertical the route traverses right to an obvious bowl feature where the ascent line is obvious but the terrain gets a bit tougher here as there's a lot more loose rock and rock that's solid is covered in kitty litter scree.
  
  Troy and I soloed this section without issue and to end it off was persistent snow patch which we were able to bypass climbers left of and above before the final steep headwall to the false summit. Some parties would likely want to rope up for this section as it's notable stiffer and still loose but it's also short lived and after topping out you're about 10 vertical meters from the top! The job wasn't finished yet though as we still had the notorious notch between us and the summit.
    
      
      
    
    
    
      
      
    
    
      
      
      
      
    
      
      
    
    
  The notch was definitely intimidating but given that we had ropes and there are bolts on either side we didn't have much to worry about, if we had been free soloing it would be a whole different story as the downclimb into the notch would be extremely exposed and committing. After rappelling into the notch Troy lead up the other side and this was probably the toughest climbing of the day. There's a bolt at the bottom so a fall wouldn't kill you but there's nowhere to place protection for the first bare section on the summit side so this is the crux! After Troy got up I didn't have much to worry about but the climbing definitely still felt tough with my disadvantage in reach. Just like that we were standing at the top of one of the toughest 11000ers in the Canadian Rockies just after 2pm and after a short break and some photos we decided to start descending as there were some distant clouds and we didn't want to chance anything with the weather, little did we know how much our fun day out was about to be turned upside down!
  
  The rappel back into the notch went without issue and with a lot more features to use on the other side we decided to solo back up to save some time and were back on the false summit of Deltaform just a few minutes later. Soon after we were back at the loose steep section we climbed to gain the false summit and with two 60m ropes we decided to go for a full 60m rap to get well past the snow below. This landed us pretty much in the guts of this bowl feature on the upper mountain where the terrain eases for a while and all that was left was to pull the rope...
    
      
      
    
    
    
    
    
    
    
      
      sure!
      
      
    Troy and I began pulling the rope and just as the end got through the anchor a number of sizable rocks were knocked loose and started barreling towards us. In typical rockfall fashion they were bouncing from side to side so it was hard to judge where they'd end up going but as they got closer it was clear they were headed for us and unfortunately Troy wasn't able to get out of the way in time. One of the rocks about the size of a dinner plate and 2-3 inches wide struck Troy on his right calf and I immediately thought he had broken his leg. The initial feeling was the worst pain he's ever felt and it took a good minute before he was able to tell me how bad it was.
    
    After things got a bit better he was able to put weight on it without too much pain so he figured it wasn't broken just badly bruised but we weighed our options and after thinking hard about it decided not to call a heli and get down on our own. Thankfully the rock had hit the more muscular part of his leg so this had likely taken a good amount of the impact, if it had hit his shin or elsewhere it's very likely our trip would've ended there and then. 
    
    After committing to getting down the mountain on our own it took a second for the seriousness of our situation to set in for me, we were just 100 vertical meters below the summit so practically at the top and still had pretty much all of the technical terrain to descend not to mention having to reascend Neptuak, the 10km of trail to Moraine Lake, and the 15km bike out. Things started out slower as the pain was still quite potent for Troy especially on any hands on terrain above 3rd class so we used every opportunity we had for rappels to avoid making his leg worse. Troy's a much stronger climber than I am so I'm used to him typically managing the rope but in this case to make things more efficient and easier for him I was setting up the rappels, rappelling and getting any tangles out, waiting for him to get down, and then coiling the rope while he limped to the next station. I got a fair bit of rope management practice on this outing.
    
    After we eventually made it back to the col we reascended Neptuak and after topping out and heading down the ridge we started feeling a few raindrops and could see that the weather was turning and this was not a good feeling given the amount of technical terrain we still had to descend. Thankfully the weather held off and through the next section Troy was feeling a bit better so he was rappelling while I downclimbed aside from a couple sections we both rappelled and once we hit the long scree section and some proper rain hit we were at least done with most of the 5th class so that was a relief. The rain had stopped again by the time we reached the nose pitch and after finishing our last rappel we both felt a huge sense of relief having gotten out of technical terrain under extremely dire circumstances. We headed for the pass and took a good break there before the slog back to the car.
  
      
      placed, I grabbed them and downclimbed
once he was down
      
      
    
    
    
    
    
    
      
      
    
      
      
    
    
    
      
      
      
  By the time we returned to Wenkchemna Pass it was almost 10pm so that should give some perspective on the pace we were going. We had gotten from the car to the summit in about 8.5hrs and to get from the summit back to the pass had taken us 8hrs so we knew we were in for a late night but we had known that long before we reached the pass. The walk out was tough cause it was completely dark by 10pm and we were moving slowly. I was nodding off as we were walking, reminiscent of the Lake O'Hara road exit I did last year for Jo and my  
  Lefroy, Victoria South, Huber linkup,
  and it's never a good time when that's happening. We made it most of the way to Moraine Lake without a break but by the time we were above the early switchbacks on the trail we were both feeling exhausted and had to take a short nap before getting the last bit done. 
  
  Once we got back to the lake we were both completely spent and I remember both of us lying down on the parking lot ground before Troy headed over towards one of the buildings next to the lake to try and warm up and I fell asleep. An unknown amount of time later he woke me up around 2:30-3am and we decided to wrap things up and do the 15km bike out which thankfully was pretty much all descending. After a quick ride out we were overjoyed to have our Deltaform epic behind us and we headed back for Canmore, probably one of the tougher drives I've done.
  
      
      
  The next morning Troy's leg was visible swollen and he made his way to the hospital to get it checked out, a few hours later he told me the news, fractured fibula. It's no understatement to say that Troy getting himself off the mountain was a hero effort and knowing now that his leg was likely broken for the entire descent makes it even crazier to imagine. Thankfully the doctors gave him a 3 week recovery time so it wasn't the worst of breaks and he didn't have to be on his feet much for the next couple weeks so things worked out!
  
  All in all this trip was a wild experience and a good example and wake up call that things can go to shit quickly in the mountains. I'll definitely be much more careful pulling the rope after rappelling in the future and I'll probably be upgrading my first aid kit as well. Following this trip I had a good week and a half gap until the next 11000er outing so this was nice to process everything and be more aware of the risks these big peaks entail but that didn't stop wild plans from ensuing with the next bluebird window and we'd be bringing the A team together to tackle the 
  toughest 11000er the Canadian Rockies have to offer!
                Other related trip reports: 
                The Goodsirs |
                Mount Alberta ||
                Mount Assiniboine & Lunette |
                Mount Fryatt |
                Whitehorn Mountain
                
                11000ers of the Canadian Rockies
            
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